Optoelectronic devices, such as image sensors and photovoltaic devices, can include optically sensitive material. Example image sensors include devices that use silicon both for the sensing function and for the read-out electronics and multiplexing functions. In some image sensors, optically sensitive silicon photodiodes and electronics can be formed on a single silicon wafer. Other example image sensors can employ a distinct material, such as InGaAs (for short-wave IR sensing), or amorphous selenium (for x-ray sensing), for the sensing (photon to electron conversion) function. Example photovoltaic devices include solar cells that use crystalline silicon wafers for photon to electron conversion. Other example photovoltaic devices can use a separate layer of material such as amorphous silicon or polycrystalline silicon or a distinct material for photon to electron conversion. However, these image sensors and photovoltaic devices have been known to have a number of limitations.